md: rename get_object_path as md_get_object_path

This is a preparation patch.

Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
plain store: refactor default_get_hash

We only need to get object path once in the first place.

Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
collie: show 'auto-recovery' status for 'cluster info'

nr_copies is removed because it isn't used at all

Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>